Laboratory container cover



Oct. 27, 1925- ATTOI lNEY.

B. P. DOPPKE LABORATORY cowl-Airing COVER Filed lay 2a 1924 Patented Oct. 27, 1925.

Bear r. norms; of mam, MICHIGAN.

J LAEOBA-TORY confirm-man COVER.-

nppl-ication filedMay 23, I924. Serial No; 715,428.

To all whom it may concern: v

Be it known that I, BERT P. "DOPP'KE, a citizen of the United States, residing at Detroit, county of Wayne, State of Michigan,- have invented a certain new and useful Improvement in Laboratory Container Covers, and declare the following. to be: a full, clear, and; exact des cripti onqof the same, such as will enable others skilled in the art to which it pertains to make and use the same, refer ence being had to the accompanying drawings, which form a part of this specification.

This invention relates to covers for containers used in laboratories, and has for its object an improved form of device adapted to at the same time protect the material, whether liquid or granular that is under examination from dust and other forei n substances being precipitated into it, and yet leave suflicient venting space at certain points above the top edge of the glass beaker to permit evaporation or vaporization to the outer air to proceed while. for example the contained substance is cooling or is awaiting the expiration of a selected time period before further analytical work is proceeded with. If a truly flat cover is used, such as a pane of glass, or a uniformly curved piece such as a saucer or watch crystal, its fiton the top edge of the container is so relatively tight that little venting or escape of the contained gases can take place. other hand, resort is had to the use of specially bent elbows 0r U-shaped pieces of glass hung in inverted position at intervals about the peripheral edge of the beaker, with the glass or other cover resting thereon, and thus spaced from contact with the edge of the container or beaker, it has been my experience that these are so easily knocked off, sometimes onto the table but more frequently into the material that is under analysis, thus polluting it, that any attempted reliance upon this means of providinga vent for the rising vapors is far from satisfactory; moreover the high temperature of some solutions, which is quickly communicated to the containeras well, often acts to so unevenly heat these, little glass pieces at their point of contact with the rim of the container, the curve or angle of their U- shape, that they often break, with equally unsatisfactory results. By the use of my improved device these objectionable results If, on the lrestricted thereto.

are avoided, while affording all the venting needed.

In the drawings: o

- Figure 1 is a perspcctiveof myi'mproved cover 131 606. y I s r Figure 2 s a sectional elevationjal view-of one ofrny cover pieces in place over the top of a container. 7 I

igureifi a sectional view of a portion ofmy cover piece showing the outstanding rib inrelation to the rest'ofthecover.

,Figure 4 is a view offa slightly modified form of ribbing for'the. cover piece.-

A represents my improved cover piece,

which is preferably though not necessarily, slightly concaved. If this were of uniform circular contour and curvature, its edges would rest uniformly on the top edge of the container C, thus affording no adequate opportunity for the vapors thrown off by the contained chemical-to escape. Furthermore, in case the edge of the container should become coated with a precipitation or residuum from the contained chemical, the uni formly engaging under surface of the cover might easily adhere thereto to an objectionable degree. To obviate this I provide on the under surface a plurality of radial ribs B, arranged at suitable intervals from one another, three such being here shown, though I do not'wish this disclosure to be These ribs resting upon the top edge of the container, whatever its diameter, provided it be less than that of the cover, actually engage an extent therealong only of the width of the rib; and these ribs preferably diminish in height as they extend inwardly toward the center of the cover piece. Between them are thus left spaces D between the rest of the covers under surface and the top edge of the glass, thus providing ample ventingspace, while avoiding all of the features of objectionability attending the previous practices described. i

The modified form shown in Figure 4- differs from the disclosure of Figure 1 in positioning its ribs F on'either side of the center rather than radially, affording, in this instance, four points of contact with the top of the container, not evenly spaced, though adequately balanced as regards the firm resting of the cover over the container.

What I claimis:

1. A cover for a container provided with spaced integral ribs on its under surface, adapted to rest upon the top edge of a container of equal or lesser diameter, thereby providing a venting space between the otherwise meeting surfaces.

2. A cover for a container, having peripherally spaced projecting ribs on its under surface adapted to engage the top edge of the container to insure the venting non-engagement of the remaining under surface of the cover with the top edge of the container.

3. A cover for a container, consisting of a top-closing piece having a plurality of spaced projecting ribs on peripherally diverse portions of its under surface, whereby, when it is rested on the top edge of a container, an intervening space is left between them at all points save where said ribs engage said top edge.

4. A venting cover for a container, having on its under surface spacedly disposed integral projections adapted to space the same from engagement with the supporting top edge of the container.

5. A cover fora container, having spacedly disposed integral ribs extending to the periphery thereof at a plurality of points on its under surface.

(3. A container cover whose under surface is of spacedly ribbed contour to effect the spacing of the rest of its said under surface from the top edge of a supporting container.

7 As a new article of manufacture, an integral cover for a container having spacedly arranged ribs projecting from its under surface, said ribs extending inwardly from peripherally diverse points at or near its edges.

8. As a new article of manufacture, a cover for a container having integral radial or tangential ribs on its under surface, whereby its body portion is suitably spaced from engagement with the edges of the container.

In testimony whereof, I sign this specification.

BERT P. DOPPKE. 

